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PC200-7 Main Relief Valve – 723-40-51102 vs 723-40-91102

Morpheus.Kratos · 2026-04-23 03:05

Hey guys,I'm trying to replace the main relief valve on a PC200-7 and I'm getting conflicting information on the part numbers.Some suppliers list 723-40-51102 as the current main relief, others show 723-40-91101 / 723-40-91102. A couple places say they're interchangeable, but I've seen one source claim the 51102 is actually a pilot/low-pressure valve and only the 91102 is the real high-pressure main relief.Has anyone dealt with this? Which one is correct for the PC200-7?I was previously told to go with the 51102, but I don't want to buy the wrong one and have issues.Anybody know the real difference between these two? Machine serial number is in the 200,000 range if that helps.Thanks!

Replies4
  1. #1John C.2026-04-23 15:23

    Have you checked with a Komatsu dealer parts department? I don't have a parts book for your machine. Can you describe or take a photo of where the relief valve is mounted? Komatsu is always updating their hydraulic components and it is likely why you are getting the different numbers but you are right to check.

  2. #2bam19682026-04-24 21:29

    My parts book shows 723-40-91101. The book is for PC200-7 sn# 200,008 and up. Although they have prob changed part #'s a time or two since the book was printed.

  3. #3Universal Parts2026-04-25 02:54

    Based on my years of sales experience, part number 723-40-51102 is generally used in machines with the SA6D95 engine, such as PC200-6, PC210-6, PC220-6, and PC230-6. Part number 723-40-91101 is generally used in machines with the S6D102 engine, such as PC200-7 and PC228.

  4. #4John C.2026-04-25 18:54

    You are kind of right but for the wrong reason. The different cartridge valve number is because of the different Dash model in the series. The Dash 6 line used both engines. The 95 series engines were generally sold outside of North America. The Cummins clone was the usual engine in machines sold in North America. There is a clue here for what you need. The last digit only identifies the update series of the part number. The initial 91101 would have updated to a 91102. That usually says there was some kind of improvement but isn't necessarily always the case. I found out some years ago the a lot of times it only means that they changed suppliers. You do want the latest you can get.